Suction device for textile machinery



Oct. 18, 1960 Filed July 2, 1957 H. R. BERBERICH ETA]. 2,956,389

suc'rxou nzvxcz: FOR TEXTILE MACHINERY INVENTORS NM ZBMMM/ BY V WWW Oct. 18, 1960 HR. BERBERICH EI'AL 2,956,389

sucnon DEVICE FOR TEXTILE MACHINERY Filed July 2, 1957 2 Sheets-Sheet 2 INVENTORS ilphuggdm $19M W substantially varied.

United States Patent SUCTION DEVICE FOR TEXTILE MACHINERY HelmutR. Berbe'rich', Westheim;Augsburg, a'ndWilly Hirschrnann, 'Marbach (Neckar Germany,-%assignms to Thoma CompanyG.m.-b.H., Augsburg, Ger- -many, a firm Filed- July 2, 1957, 'Ser."1N0. 669,605

Claims priority, applicatiomGermany July-2, 1956 6 Claims. (Cl. 57- 3415) It is known in devices for sucking upbro'ken'thread ends in spinning machines,to provide thesuction'ttibes not only witha circular cross-section'but also with a cross-section tapering towards the suction apertures,in order thus to bring the suction apertures more effectively into the angle between the last lower drafting frame roller and the outgoing thread, or to shift the said suction apertures nearer to the nip .point. However the known suction tubes of tapering cross-section do not vary considerably from a round or oval or pear-shaped cross-section, so that the flow conditions in the suction'tube are not 'It has now been found that in spinning synthetic material or rayon staple with a longstaple fibre, thread breaks occur when usingthe known suction tubes specified hereinbefore, so that these prior known suction tubes are not suitable for material having a long-staple fibre (over 40 mm. in length).

The object of the invention is to provide a suction tube which is suitable not only for spinning threads having a short-staple fibre, but also for spinning material having a long-staple fibre. For this purpose, according 9, I0, theplane walls"9 and10'of the main duct'merging to the invention, the cross-section of the shaped suction tube is so sub-divided into a rounded main duct and a narrow and elongated nozzle duct that the suction current rotating in the main 'duct of the suction tube cannot .act on the nozzle duct.

The invention will now be explained in more 'detail' hereinafter with reference to an example of an embodiment illustrated in the drawings, wherein:

'Fig. l is a side view of a spinning-machine drafting frame provided with a suction tube, 'the latter being shown'in cross-section;

Fig..2.is a plan view one natural scale of the suction .tube .ofFig. 1; and

.Fig. 3 is a front view in the direction D of Fig. 1.

Reference numeral 1 designates a roller stand ofthe drafting frame, and 2, 3 designates the last pair of drafting rollers. The thread travelling through the drafting frame isindicated *by'a chain-dotted line" a.

As the drawings show,.a suction tube isprovided which comprises a plurality of suction apertures 4, has aconstant cross-section throughout and tapers towards the suction apertures, the substantially L shaped cross-section of the said tube being inflected at abtuse angle 0c. The .L-shape of the cross-section is formed by a relatively narrow nozzle duct '5 and a substantially wider main .duct'6. The configuration'ofthe suction tube cross-section is sozchosen'thatthesuction current, whichrotates tin themain .duct'and Whoserc-tnry flow is indicated by "the arrows A, 'cannot'act'onthe narrow nozzle duct 5.

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suction apertures 4 from coming into contact through these suction apertures with the aspirated fibrous material of a broken thread, so that in this way further thread breakages are effectively prevented.

In the illustrated advantageous embodiment, .the length l of thenozzle duct 5 is a multipleof the width b of the said duct, whereas the mean width B of'the main duct 6 is at least twice as, great asthe-mean width b.

'Moreover, the nozzle duct and main duct are advantageously bounded substantially by plane walls 7, Sand tangentially into the arcuate-Wall '11'of the suction tube. This configuration achieves a clear separation between the main duct 6 and the 'nozzle duct'5. In spite of the illustrated bend in thesuction tube cross-section, the flow conditions are in no way detrimentally influenced, i.e.,.a broken thread sucked in through an aperture 4 into the nozzle duct 5 isnotdrawnround the bend in the suction tube but onthe contrary when sucked into the nozzle duct '5 is drawn downwardsvertically and is then seized at 12 by the suction current A rotating in the main duct fi.

Thus the new shaping of'thesuction tube affords entirely favorableflow conditions, corresponding to those of a round suction tube. The novel suction tube has also a comparatively large overall cross-section of approximately 700 mm. i.e., thisoverall cross-section corresponds to the hitherto conventional round suction tubes having a diameter of 30 mm.

The novel suction tube is also movably mounted.

The end pins13 of the suction tube are advantageously mounted in arcuate guide slots "14 of fixed bars '15, so that the suction tubes can be slid downwardly and'rearwardly e.g.,' for the purpose of cleaning the drafting'frame rollers.

The suction tubes are connected by piping 16 in known manner, by means of a rubber sleeve, to the collecting conduit of the suction apparatus.

The suction tube described hereinbefore has'the further advantage that no deposits of dust, etc. will form in the vicinity of the aperture 4 on the lateral Walls of the nozzle duct 5, i.e., even after a long operational period, hence blockages and'therefore breakdowns in operation are avoided. Furthermore the special shaping of the suction tube imparts a considerable rigidity thereto, both against bending stresses and against torsional stresses.

We claim:

1. A suction device for aspiration of broken thread ends in a textile machine, comprising in combination, an elongated suction tube of substantially uniform L-shaped cross section, the legs of said L-shape constituting respectively a main duct portion and a nozzleportion'narrower than said duct portion, said nozzle portion being formed with a plurality of openings spaced from said duct portion, said nozzle portion increasing in cross-sectional area from said openings in said'nozzle portion in the direction toward said main duct portion, said main duct portion and said nozzle portion being joined to each' other in the region wheretheir central planes intersect; and a connecting conduit communicating with said main duct portion at a point along the length thereof for connecting said suction tube to a source of negative pressure, whereby a fluid aspirated through said plurality of openings will flow through said nozzle portion. in a substantially smooth flow pattern toward said main duct portion, and any turbulence existing in said main duct portion is substantially prevented from iniiuencing the pattern of flow in said nozzle portion.

2. A suction device for aspiration of broken thread ends in a textile machine, comprising in combination, an elongated suction tube of substantially uniform L-shaped cross section, the legs of said L-shape constituting respectively a main duct portion and a nozzle portion narrower than said duct portion and defining therewith an obtuse angle, said nozzle portion being formed with a plurality of openings spaced from said duct portion, said nozzle portion increasing in cross-sectional area from said openings in said nozzle portion in the direction toward said main duct portion, said main duct portion and said nozzle portion being joined to each other in the region Where their central planes intersect; and a connecting conduit communicating with said main duct portion at a point along the length thereof for connecting said suction tube to a source of negative pressure, said 'main duct portion increasing in crosssectional area from said nozzle portion toward the end of the respective leg of the L-shape, whereby a fluid aspirated through said plurality of openings will flow through said nozzle portion in a substantially smooth flow pattern toward said main duct portion, and any turbulence existing in said main duct portion is substantially prevented from influencing the pattern of flow in said nozzle portion.

3. A suction device for aspiration of broken thread ends in a textile machine, comprising in combination, an elongated suction tube of substantially uniform L-shaped cross section, the legs of said L-shape constituting respectively a main duct portion and a nozzle portion narrower than said duct portion, said nozzle portion tapering in a direction away from said main duct portion and being formed with a plurality of openings in the part thereof farthest from said main duct portion, said suction tube having a convex outer wall and a concave inner wall, said convex outer wall forming an obtuse angle having its apex where said nozzle portion joins said main duct portion; and a connecting conduit communicating with said main duct portion at a point along the length thereof for connecting said suction tube to a source of negative pressure, said main duct portion increasing in cross-sectional area from said nozzle portion toward the end of the respective leg of the L-shape, whereby a fluid aspirated through said plurality of openings will flow through said nozzle portion in a substantially smooth flow pattern toward said main duct portion, and any turbulence existing in said main duct portion is substantially prevented from influencing the pattern of flow in said nozzle portion.

4. A suction device for aspiration of broken thread ends in a textile machine, comprising in combination, an elongated suction tube of substantially uniform L-shaped cross section, the legs of said L-shape constituting respectively a main duct portion and a nozzle portion narrower than said duct portion, said nozzle portion being formed with a plurality of openings in the part thereof farthest spaced from said duct portion, said suction tube having a convex outer wall and a concave inner wall, said convex outer wall forming an obtuse angle having its apex Where said nozzle portion joins said main duct portion, and said main duct portion having in the part thereof farthest spaced from said nozzle portion a rounded wall; and a connecting conduit communicating with said main duct portion at a point along the length thereof for connecting said suction tube to a source of negative pressure, said main duct portion increasing in cross-sectional area from said nozzle portion toward the end of the respective leg of the L-shape and toward said rounded wall, whereby a fluid aspirated through said plurality of openings will flow through said nozzle portion in a substantially smooth flow pattern toward said main duct portion, and any turbulence existing in said main duct portion is substantially prevented from influencing the pattern of flow in said nozzle portion.

5. A suction device for aspiration of broken thread ends in a textile machine, comprising in combination, an elongated suction tube of substantially uniform L-shaped cross section, the legs of the said L-shape constituting respectively a main duct portion and a nozzle portion narrower than said duct portion, the length of the cross section of said nozzle portion being a multiple of the width thereof, and the mean width of the cross section of said main duct portion being at least twice said width of said nozzle portion, said nozzle portion being formed with a plurality of openings spaced from said duct portion, said suction tube having a convex outer wall and a concave inner wall, said convex outer wall forming an obtuse angle having its apex where said nozzle portion joins said main duct portion; and a connecting conduit communicating with said main duct portion at a point along the length thereof for connecting said suction tube to a source of negative pressure, said main duct portion increasing in cross-sectional area from said nozzle portion toward the end of the respective leg of the L-shape, whereby a fluid aspirated through said plurality of openings will flow through said nozzle portion in a substantially smooth flow pattern toward said main duct portion, and any turbulence existing in said main duct portion is substantially prevented from influencing the pattern of flow in said nozzle portion.

6. A suction device for aspiration of broken thread ends in a textile machine, comprising in combination, an elongated suction tube of substantially uniform L-shaped cross section, the legs of said L-shape constituting respectively a main duct portion and a nozzle portion narrower than said duct portion, said portions having substantially plane side walls, the side walls of said main duct portion tapering in a direction toward said nozzle portion and being joined by an arcuate end Wall, said side walls being substantially tangential to said end wall, said nozzle portion being formed with a plurality of openings spaced from said duct portion, the side walls of said nozzle portion tapering away from said main duct portion and toward said openings, the side Walls of both said portions extending, respectively, at obtuse angles to each other and being connected along longitudinal lines at the apex of the L-shape; and a connecting conduit communicating with said main duct portion at a point along the length thereof for connecting said suction tube to a source of negative pressure, whereby a fluid aspirated through said plurality of openings will flow through said nozzle portion in a substantially smooth flow pattern toward said main duct portion, and any turbulence existing in said main duct portion is substantially prevented from influencing the pattern of flow in said nozzle portion.

References Cited in the file of this patent UNITED STATES PATENTS France July 22, 1953 

